MeasurableTuiNodeRendererInterface

A renderer that can say how tall its node WOULD be, before anything is drawn. ── WHY THIS EXISTS ───────────────────────────────────────────────────────────────────────────── The vertical layout splits the available rows evenly between children that declare no `height`. That is right for a dashboard, where every panel deserves a share, and wrong for a conversation: the more that has been said, the less of each thing you see — exactly when there is most to read. A conversation does not divide, it scrolls. A caller can only scroll if it knows how tall each entry is, and the only honest source of that number is the renderer that will draw it. Anything else is a second implementation of wrapping that agrees with the first until the day it doesn't — and the disagreement shows up as text silently missing from the screen, which is the hardest defect in a TUI to even notice. ── WHY OPTIONAL, AND NOT PART OF THE MAIN INTERFACE ──────────────────────────────────────────── Not every renderer can answer. A node that draws a fixed box knows its height; one that streams has no answer until it has streamed. And `TuiNodeRendererInterface` is published — widening it would break every renderer written outside this repository, for a capability most of them do not need. Callers ask with `instanceof` and fall back when the answer isn't available.

abstract public function measureHeight(Milpa\Live\ValueObjects\Tui\TuiNode $node, int $width): int

How many rows this node needs at `$width`, with no height limit. The number is what the renderer WOULD produce, not what it will be allowed to draw: the caller is asking precisely so it can decide how much room to grant.

Parameters